Wall-mounted dispensers for liquid products are well-known in the art. Typically, they include a wall-mounted housing that can be opened to receive liquid product containers. Many times, these liquid product containers are part of a refill unit that includes the product container and a pump mechanism. Once placed in the housing, an actuator mechanism, often a push bar or a electronic system actuated by a proximity sensor, can be manipulated to actuate the pump and cause a dose of the liquid product to be dispensed to the user's hand.
For customer satisfaction, it is important that such wall-mounted dispensers do not go empty. Thus, it is necessary to periodically replace an empty or near-empty product container/refill unit. Such periodic replacement demands maintenance time. The maintenance time and frequency of maintenance visits may be minimized by attending to the replacement of all near-empty containers/refill units during a given maintenance visit. But replacing a near-empty container with a new, full container, while being effective in preventing the occurrence of an empty dispenser, results in waste of the product still remaining in the near-empty container. Thus, though maintenance time may be saved by replacing all near-empty containers/refill units during a given maintenance visit, the cost of the wasted product must be weighed against the potential savings in maintenance time. At any rate, the dispensing systems would benefit from more consistently providing a dispenser that contains product.
To address this problem, some dispensers are configured to hold two or more refill units at one time. However, it is typically necessary to pull a lever or turn a knob in order to switch the actuator mechanism from association from one refill to associate with the other. As a result, these dispensers have not been commercially successful because they are not received well by the end users, who must know what to do to switch from an empty container to a non-empty container. Thus, a need exists in the art for a dispenser that can receive two refill units and that provides an actuator mechanism that automatically switches from an empty refill unit to a non-empty refill unit.
One area of liquid dispensing that is quite popular is soap and sanitizer dispensing. In recent years, it has become popular to dispense soap and sanitizer products as foam, wherein a liquid soap or liquid or gel sanitizer is mixed with air. To dispense the liquid product as a foam, both a liquid pump and an air pump are typically employed, and, in the case of a refill unit carrying the pump mechanisms, it is common to provide both the air pump and the liquid pump as part of the refill unit. Thus, the need for a dispenser that automatically switches between an empty and a non-empty refill unit would also benefit by being capable of dispensing the product in the refill unit as a foam. Further benefits might be realized by providing an air pump portion as part of the dispenser, thus permitting the refill units to simply hold liquid pumping mechanisms.